Cosmo K10101C(PC817C) 4PIN PHOTOTRANSISTOR PHOTOCOUPLER
The K1010 1C (often written as K10101C) is a 4-pin phototransistor optocoupler (photocoupler) manufactured by COSMO Electronics. It is widely used for electrical isolation between high-voltage and low-voltage circuits, serving as a direct equivalent to the industry-standard PC817C integrated circuit.
